Fluid driven motors are known in the art which utilize elevated pressure or elevated velocity gases, such as air, to cause a shaft to rotate so that work can be done. Some prior art devices date back to around 1873, when steam power systems were being developed. In general, the high velocity fluid driven motors include a fixed vane rotor and a fixed vane stator. A nozzle directs the high velocity air against the fixed vanes of the rotor, causing rotor rotation. Such fixed rotor fluid driven motors generally exhibit extremely high free speeds, speeds exhibited when no load is placed on the motor, especially when sized to be hand held.
Many different types of fluid motors are known in the art that have been used with many different liquids and gases, including steam, compressed air and water. One type converts a high velocity stream of fluid (kinetic energy type) into mechanical rotation. These range from large water turbines that are used in hydroelectric generating plants and aircraft jet engines to very small dental drills that are used in filling teeth. The speed of a turbine dental drill ranges from 500,000 to a million RPM, and produces a very low torque. The jet engine typically turns at approximately 25,000 RPM and produces a high torque by having many stages of redirection of the gas stream and many expansion stages.
Another common type of motor uses static fluids under pressure to produce mechanical motion (potential energy type). Typical motors of this type use pressure against pistons to produce motion. Examples of this type include automobile engines and steam locomotives. Another type of static fluid pressure motor does not require a crank or similar mechanism to convert the fluid pressure to shaft rotation. In these motors, often referred to as a vane type, the pressure is applied directly against the vanes, which are coupled to the shaft. In contrast to pistons which have a fixed area exposed to the fluid pressure, the well known vane motor presents an area that ranges from zero to a maximum, in half of a revolution.
These prior art rotors which rely on static fluid pressure include a dynamic rotor having flat vanes which slide away from and toward a geometric center of the rotor. The rotor is located asymmetrically within a cylinder such that air passing from an inlet to an outlet within the cylinder causes the rotor to rotate in only one direction. The vanes slide away from and toward a rotational axis of the rotor as the rotor rotates. Because such sliding flat vane rotors contact a wall of the cylinder, friction exists which determines a maximum free speed of the rotor for a given air pressure. Such motors also exhibit relatively high torque at lower speeds than high velocity air motors.
While such sliding flat vane rotors are useful for many applications, some applications require higher torque at still lower speeds than those obtainable with flat sliding vane rotors. bearing the output shaft to obtain desired speeds is often excessively complex or expensive for many applications. The sliding vanes are also constrained geometrically to exhibit only slight extension, to prevent excessive shear stress on the vanes. Additionally, flat sliding vane rotors require some form of system to extend the vanes away from the rotor at start up, before centrifugal forces can be utilized to maintain the vanes against a surrounding cylindrical wall. The fluid pressure does not inherently cause the vanes to extend. Finally, such flat sliding vane rotors must be formed with multiple pieces and to precise tolerances to ensure that the vanes can effectively slide within slots in the rotor. Accordingly, a need exists for a fluid driven motor or fluid reaction device which has high torque at low speeds but which is sufficiently easily manufactured to facilitate economical disposability and has vanes which extend readily when the device is started. Additionally, a need exists for a fluid reaction device which has a high torque at low speeds without the use of gears.
The following prior art reflects the state of the art of which applicant is aware and is included herewith to discharge applicant's acknowledged duty to disclose relevant prior art. However, it is respectfully submitted that none of these prior art devices teach singly, nor render obvious when considered in any conceivable combination, the nexus of the instant invention as especially claimed hereinafter.
______________________________________ INVENTOR PATENT NO. ISSUE DATE ______________________________________ Schmitz 263,814 September 5, 1882 Current 1,343,115 June 8, 1920 Kochendarfer 1,601,397 September 28, 1926 Swisher, et al 1,999,488 April 30, 1935 Wiseman 2,017,881 October 22, 1935 Roelke 2,025,779 December 31, 1935 Monnier, et al. 2,128,157 August 23, 1938 Blair 2,135,933 November 8, 1938 Smith 2,226,145 December 24, 1940 Goldenberg 2,300,828 November 3, 1942 Shotton 2,315,016 March 30, 1943 Greenberg 2,328,270 August 31, 1943 Moore 2,463,118 March 1, 1949 Wiseman 2,789,352 April 23, 1957 McFadden Re. 24,391 November 12, 1957 Kern 2,937,444 May 24, 1960 Quackenbush 3,043,274 July 10, 1962 Wiseman 3,163,934 January 5, 1965 Winkler 3,192,922 July 6, 1965 Hoffmeister, et al. 3,229,369 January 18, 1966 Burnett 3,376,825 April 9, 1968 Brehm, et al. 3,421,224 January 14, 1969 Smith 3,510,229 May 5, 1970 Graham 3,727,313 April 17, 1973 Brahler 3,740,853 June 26, 1973 Booth 3,855,704 December 24, 1974 Campagnuolo, et al. 3,856,432 December 24, 1974 Killick 3,877,574 April 15, 1975 Balson 3,955,284 May 11, 1976 Danne, et al. 3,987,550 October 26, 1976 Flatland 4,053,983 October 18, 1977 Gritter 4,1,71,571 October 23, 1979 Girard 4,182,041 January 8, 1980 Lewis 4,248,589 February 3, 1981 Warden et al. 4,259,071 March 31, 1981 Melcher 4,261,536 April 14, 1981 Warden et al. 4,266,933 May 12, 1981 Bailey 4,365,956 December 28, 1982 Karden 4,465,443 August 14, 1984 Geller 4,693,871 September 15, 1987 Buse 4,767,277 August 30, 1988 Choisser 4,795,343 January 3, 1989 Choisser 4,842,516 June 27, 1989 Stefanini 4,863,344 September 5, 1989 Moreschini 4,929,180 May 29, 1990 Kimura 4,941,828 July 17, 1990 Huang 5,020,994 June 4, 1991 Witherby 5,028,233 July 2, 1991 Falcon et al. 5,040,978 August 20, 1991 Rosenberg 5,062,796 November 5, 1991 Bailey 5,094,615 March 10, 1992 Butler 5,120,220 June 9, 1992 Bailey 5,156,547 October 20, 1992 FOREIGN PATENT DOCUMENTS DOCUMENT SUB- FILING NUMBER DATE NAME CLASS CLASS* DATE ______________________________________ 12584 03/1903 Munson 418 225 (Sweden 646,193 06/1937 Durhager 30b 202 5/1937 (Germany) 803,306 07/1949 Hollmann 418 225 (Germany) 102,433 05/1951 Callaghan 433 132 (New Zealand) GB 2 209 284-A 05/1989 Kalsha A61C 1/05 07/1988 ______________________________________